


Quantum Entanglements

by antigrav_vector



Series: (R)BB fics - all pairings [17]
Category: Captain America (MCU), Iron Man (MCU), Marvel, Marvel Cinematic Universe, The Avengers (2012)
Genre: Alternate Universe - Canon Divergence, Bucky Barnes Recovering, Bucky is better adjusted than Steve somehow, Canon-Typical Violence, Comic Book Science, Get Together, I can't even with these idiots, M/M, Mission Fic, Missions Gone Wrong, POV Tony Stark, Polyamory Negotiations, Post-Captain America: The Winter Soldier, Post-HYDRA Reveal, References to PTSD, References to Panic Attacks, Steve has some unresolved anger issues, deliberately unresolved subplots
Language: English
Status: Completed
Published: 2018-06-04
Updated: 2018-06-09
Packaged: 2019-05-18 06:27:12
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 7
Words: 11,531
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14847512
Author URL: https://archiveofourown.org/users/antigrav_vector/pseuds/antigrav_vector
Summary: A few weeks after the events of CA:TWS, the team is sorting out the HYDRA bases they've discovered as a result of the data dump Steve and Nat did. What happens next, well. Not even Tony Stark, futurist, could have predicted that.





	1. Chapter 1

**Author's Note:**

  * Inspired by [[ART] Lab Partners](https://archiveofourown.org/works/14852060) by [potofsoup](https://archiveofourown.org/users/potofsoup/pseuds/potofsoup). 



> Presented with thanks to my beta reader [archofimagine](https://archiveofourown.org/users/ArchOfImagine/works) and artist [potofsoup](http://potofsoup.tumblr.com/).

He probably should have known better than to let Cap convince him to investigate the labs of the apparently abandoned HYDRA base. They'd been cropping up all over the continent -- well, all over the world really, but the team didn't have jurisdiction outside North America -- and Cap had been insisting that the team investigate each and every one they legally could, as well as a few that they technically couldn't, almost rabidly searching for clues to the location of his WWII bestie, Barnes. Who was apparently the Winter Soldier.

Cap had been real broken up over having to fight Barnes -- Tony had seen a little of that while Cap was laid up recovering from it -- and then apocalyptically angry at any and everyone that might have been even tangentially responsible. In the course of his fevered searches, he'd turned up a number of HYDRA bases and all kinds of hidden financial assets that he'd done his best to destroy without leaving his bed. The team felt it, too, to a degree -- and nevermind that none of them had had anything to do with Barnes' 75 year stint as a POW -- what with the way Steve turned right around and poured all that emotion into what he considered productive things.

And, sure, Tony could guess that it had been Cap's pent up frustration and desire to help his friend that was causing the screaming matches, brooding, and everything else. He was frustrated and it showed. They bickered and argued all the time, but it was normally nothing like this. Those were like sparks. Flares of annoyance that vanished almost the moment they both turned away from the 'discussion'. This was more like glowing forge coal, smouldering and ready to burst back into flame at the least provocation.

But Tony had spent that week doing _so much damage control_. Both political and physical. After DC, everyone who was anyone had been out for blood. Steve's, Romanov's, SHIELD's, it didn't matter. Someone's head had to roll, after what had happened, and Tony'd had his hands full for literal days trying to keep his teammates from getting eaten alive. He wasn't sure he would ever quite forgive Steve for that little stunt. Or Romanov.

In the week or so Steve was forced to spend healing after dropping the SHIELD helicarriers into the Potomac and all of SHIELD's files onto the internet, he'd driven every last one of his visitors crazy. Including Wilson.

Worse, the constant attempts on Steve's part to strategise and attempt to logic out what Barnes might do had very nearly succeeded in convincing Steve he needed to get out of his hospital bed to run off and search for his long lost bestie.

It had been something of a relief when Cap had finally been recovered enough to take action again. Things between them had eased again almost instantly -- and Steve had looked almost embarrassed -- when that had happened, but no one openly acknowledged Steve's possible rage issues. Tony privately thought Steve needed to take a few pointers from Bruce, once they could track him down long enough to ask.

In the meantime, though, Romanov had handed Cap a file whose contents were unknown to Tony, and that had led to Cap vanishing into his apartments for a week. He'd also destroyed the reinforced gym in Stark Tower three times during that week, but hey who was counting. Tony had been kind of relieved that it hadn't been his face or his armour getting demolished. Steve had a tendency to forget his strength if they attempted to spar while he was truly riled up, though thankfully that didn't happen too often and he always wallowed in guilt afterward. Steve tended to save his strength for their missions, and pour his bottled up emotions out on their enemies. Having found out that his bestie had been stuck in their enemies' hands for something like 70 years, though... Yeah. That had set him off in a big way, and Tony had no doubt that anything HYDRA-affiliated that crossed Steve's path would get razed to the ground and the remains salted, after this.

He did have a habit of piling on extra training sessions for those team members who got on his nerves, though, and usually that meant sparring sessions with him.

But a few hours after his self-imposed isolation was over, Cap's anti-HYDRA crusade had picked up again with new fervor.

It had led the team here, to the asscrack of nowhere, North Dakota, where HYDRA had turned a bunker built during the Cold War into a goddamn rabbit warren of underground tunnels, storerooms, labs, and who even knew what else.

The team, which was comprised of Tony, who'd been deputised to sort through the labs and computer systems as the team's resident tech expert, Cap and Romanov, who'd taken on dealing with the rest of the base, and Wilson and Barton, their lookouts. 

Tony surveyed the fifth lab he'd hurriedly searched through and bit back an aggravated sound. He wished Banner had been available for this. The labs here were definitely much more geared toward squishy science research than tech. And, sure, he knew a little about that kind of thing -- he'd learned it in a hurry after Yinsen had put the reactor in him -- but it wasn't his forte. Not like it was Bruce's.

"Still clear, Hawkeye?" Cap's voice came through the comms reasonably clearly. He sounded annoyed again. Probably hadn't found anything worth mentioning in the base's records or whatever he'd gone after.

"Still clear," Clint confirmed. "Just fucking cold and snowy. Do us a favor and try not to waste too much time in there."

"What he said," Sam agreed. "My wings are gonna ice over soon, at this rate. Why did I agree to go on a mission with y'all in January, again?"

Tony sniffed. "My designs aren't that shitty, Falcon," he put in.

"Chatter," Romanov reminded them brusquely.

Not bothering to reply and ignoring Barton's protests, Tony moved on to the next lab in what felt like an endless series of identical rooms with little of note inside them, and stopped in his tracks. "Uhhh, guys? You might want to come see this."

Cap tried to reply, but the comm was suddenly distorted and difficult to understand. Tony couldn't find it in him to care about that at the moment. There was a massive machine in the center of this lab, taking up most of the floorspace, and whatever it was, it was making his suit throw up all kinds of errors and alerts. Exotic particle radiation (fairly harmless), radio (probably what was interfering with the comms), microwaves (also possibly causing interference), and a signature that JARVIS was telling him matched Loki's staff.

He approached the thing cautiously. He was the best qualified of the team to deal with unknown tech, anyway, so it would matter little if he got a head start while the others cleared the rest of the base and made their way to join him.

"So," he said to it, trailing one gauntleted hand over the control panel, "tell me all your secrets."

None of the buttons were labeled. Well, he amended the observation, not anymore. There had perhaps been labels once, but they'd all been worn away. That implied this thing -- whatever it was -- had either seen a lot of use, or the control panel had been scavenged from some other piece of equipment. Tony wasn't sure which was worse.

Abandoning that line of interrogation for the moment, he circled the contraption. It looked like nothing more than a Rube Goldberg machine, really. There were tangles of exposed wiring going every which way, and sockets for who knew what peripherals. Alligator clips, voltage and current readouts, and batteries were scattered over the 'surface' of the thing, and none of those was labeled either.

The whole thing was going to be an utter nightmare to try to analyse, from top to bottom. Tony bit back a groan. The only useful information he'd gotten so far was that the power signature matching Loki's glowstick of doom was buried somewhere in the middle of that mess.

"Any ideas, J?" He prompted.

JARVIS sent back the equivalent of an auditory shrug. "Analysis of the armour's visual feed is inconclusive, I'm afraid. Further information is needed, if I am to assess this device's capabilities with any degree of reliability, Sir."

"Figures." There was nothing for it, really; he'd have to turn the thing on and start pushing buttons if he wanted to know what it was or what it did. How it worked would take months, if he wanted to make the attempt.

Methodically starting to work from the top left corner of the control panel to the bottom right, he tried all the green buttons first. Those were often power switches, after all. He got lucky on his fourth try, and JARVIS helpfully labeled it on his HUD. Whatever the thing was, it started up with a hum he felt in his bones. "Huh. Okay. That's vaguely ominous."

JARVIS huffed at him. "It is a device of unknown capability, designed and built by HYDRA, Sir."

He continued working through the green buttons, starting over this time. The hum changed in pitch a couple of times, but there was no other obvious change.

"Iron Man," Steve asked, stepping through the doorway, "what have you found?"

"So far?" Tony answered, briefly turning to face his team lead, "A whole lot of nothing. I'm not convinced this thing is more than just a glorified paperweight, its dimensions notwithstanding."

Steve frowned. "It's not like them to build something this elaborate for no reason."

"I never said they built it for no reason," Tony shot back, turning back to the control panel and pushing a few more buttons with short pauses in between each so that JARVIS could log any changes in the machine's state. "Only that I know nothing about what it does. Or, rather, what it's supposed to do. Might be they weren't finished debugging and beta testing this thing."

"But--" Steve started.

Tony looked up when Steve's words cut off. Steve was staring down at the shield on his arm, his eyes round. "What is it, Cap?"

"I-- It's vibrating. That's never happened before."

Tony stepped away from the control panel and over to Steve, his footfalls ringing quietly on the concrete floor. "That's weird. Vibranium is supposed to absorb and damp vibrations."

As he approached Steve, he could feel the vibrations building, himself. The power source of his arc reactor was vibranium, too. And for all that it was a small amount, and not embedded in his sternum anymore, it was like turning his phone on silent and laying it on his chest while it rang. The vibrations intensified as he approached Steve, for no identifiable reason, and that made Tony frown. He stopped when he got into conversational range, about a meter from Steve, and opened his mouth to say something.

Before he could say a word, though, there was a bright blue-white flash, and a thud, followed by a pained groan that wasn't in Steve's voice and a loud bang that could only have come from the machine. A glance at the room made Tony freeze.

Steve was rubbing at his eyes with a pained expression, a trickle of smoke rose from the machine, the humming had stopped, and a guy Tony didn't recognize lay sprawled on the floor between them. "Cap?"

"Yeah?" Steve sounded exhausted, his voice hoarse.

"Look down." Tony didn't take his eyes off the guy, who was dressed in black body armour from head to toe and bristling with enough weapons to fill a small armoury. He also, Tony noted with a mix of alarm and glee, seemed to have a metal arm.

It took Steve a moment to do as Tony had suggested. And by then the stranger was climbing unsteadily to his feet.

"Bucky?" Steve sounded winded, like he'd been suckerpunched.

The query got a low voiced growl in reply. "Damn it, I've told you before. That's not my name."

Tony couldn't help but laugh. "Of all the bars in the world," he quoted, and got a halfhearted glare from Barnes. And he was pretty sure it _was_ Barnes and not the Winter Soldier that stood before them. "Now that you're here, come on back to New York with us," he suggested and ignored the continued irritated wordless grumble coming from the guy. "Save us all a heap of trouble when Cap goes haring off after you again, and give HYDRA a collective headache by joining forces with me."

"You-- Tony!" Steve sounded stunned. "That isn't--"

"Shut up," Barnes told him curtly, cutting him off mid-sentence, his eyes on Tony's mask focused an intent, "this ain't your deal to negotiate. What are you offering, Stark?"

Tony considered that for a moment, then flipped up his faceplate. Steve made a reflexive sound of protest that he and Barnes summarily ignored.

"What I'm offering?" Tony replied picking his words carefully, "I'm offering to fix up that arm of yours, and strip out whatever trackers are pretty much guaranteed to be in it." He saw the tiny flinch Barnes did his best to hide. Yeah, he knew the trackers were there, and was surely doing all he could to jam them. "I'm offering to build you tech tailored to you. I'm offering you a home base, as well as room and board. I'm offering you a lifeline, is what I'm doing, Barnes. Take it or leave it. But between you and me? Our forces combined? We would be almost unstoppable against any force you choose to name, including HYDRA. Throw in Cap and the rest of the team, and no one stands a chance."

Barnes tried to stare him down, but after years of Board meetings, interviews, Pepper, Rhodey, Obie, Nat, Fury, Coulson and the Cap, it barely made a dent in Tony's mask. He'd had plenty of practice. After about a minute, Barnes huffed and growled a few more curses under his breath. "You've got yourself a deal," Barnes said grudgingly, though Tony could hear an undertone of relief. "But double cross me, and I won't hesitate."

He didn't specify what he would do, but Tony felt the shiver run up his spine anyway. He smirked and offered his gauntleted left hand for Barnes to shake, pointedly making sure that Barnes would have to use his prosthetic if he wanted to seal the deal. "Noted."

Turning to Cap, who was still watching them, speechless, Tony added. "Come on, let's blow this thing up and go home."

Steve nodded, and lifted a hand to his ear as he spoke into the comms. As Steve turned away to organise the base's demolition, Tony gave Barnes a once-over from head to toe, and raised an eyebrow at him. "You going to come back to the Tower with us or travel there yourself?"

"Just how trusting do you think I am?"

"Touché. When can I expect you, then?" Tony accepted that without argument.

Looking like he hadn't expected Tony to agree to that, he paused to consider. "Four days."

"From now?"

"Do you need everything spelled out? I thought you were supposed to be a genius?" Barnes jibed.

Laughing, Tony shot back. "Well, you weren't kidding; you're definitely not trusting. It helps to be specific about certain things like that. Come on, gimme a date and time."

"Four days." Barnes said again, stubbornly sticking to his initial 'offer', and exited the room.

"Buck--!" Steve tried to go after him, and fetched up against Tony's outstretched arm. They both staggered a bit.

"Let him go, Steve," Tony told his friend in a low voice. "Chasing after him now will only scare him off of actually following through on what he offered."

With a deeply frustrated growl of his own, Steve grabbed him by the shoulder and forced Tony to meet his eyes. "Fine, we'll do it your way, but Tony, if you bet wrong just now, I will not be pleased, and neither will you. That was the best chance I've had yet to get him back."

Tony had to roll his eyes. What a pair of drama queens. "Calm your ass the hell down and give him a chance," he replied, knowing his tone was honed to a fine edge. "I know you want him back badly enough to burn down D.C. a second time, but that won't help your case or his. You're still high on the America's Most Wanted list despite all the damage control I've been doing."

Natasha walked into the room, then, and Steve stormed out.

"Are you done here?" She asked Tony, a smirk tugging at her lips that implied she'd overheard most of the discussion, if not all of it.

"Yeah."

"Then help me wire up this room," she said and handed him a portion of her remaining explosive charges. "We're bugging out as soon as that's done." 

"And thank fuck for that," Clint put in. "I'll be happy if I never see this part of the country in winter ever again."

Tony spared a moment to wonder how Barnes was going to slip past their pair of lookouts -- or whether he already had -- then put the thought aside and started planting his share of the bombs.

It didn't take long, and at about the same time they finished, Sam whistled lowly. "Wow, Cap looks pissed. What the hell happened in there? We only got one side of the conversation."

"Tell you later," Tony headed that off at the pass. "Let's get back to the Tower first."

"Wow, something big went down, didn't it." Clint laughed, sensing juicy gossip. "You two having a lover's spat?"

Tony groaned, drowning out Cap's irritated growl. "How many times do we have to tell you we're not an item, Barton?"

"At least a few more. You sure act like one, right down to the yelling. Platonic life partners, or whatever that crap is called, nowadays." Hawkeye sounded utterly unrepentant, despite playing with fire. Tony was pretty sure that Steve was already starting to tally up those extra training sessions he was infamous for assigning to team members he thought needed to practice. It was a way of keeping them in fighting form and letting Steve work out his frustrations in the most efficient way he knew.

The 'platonic life partners' quip stung a little, despite his best efforts. Tony had to admit, it probably did look like they were, from the outside, with the way they leaned on one another for so many things. Steve made him believe he could be better, even though the media kept dredging up his past. Made him want to be. And Steve looked to him for orientation in the foreign cultural territory of the twenty-first century.

But the point remained that they weren't a thing, and likely never would be despite his potential interest in such an arrangement. Not now that Barnes was back in Steve's life and likely to move into the Tower with them. Without bothering to respond to Hawkeye's comment -- let Steve do it if he felt the need; Tony was done with the discussion -- he hit his thrusters and jetted off for home. "I'll see you back at the Tower."

"Really, guys?" Falcon complained, "Y'all gotta rile Cap up and then put me on a plane with his grumpy white ass?"

"Just keep your mouth shut, Wilson," Nat commented with a smirk coloring her voice. "Steve knows better than to shoot at innocent bystanders."

Tony gave JARVIS the command to shut off the team comms as the lead between him and the team grew, then turned his attention to more immediate problems. "J, we got a suite suitable for Barnes available?"

"Not at present," his AI replied. "But given the timeframe Sergeant Barnes specified, I believe we can remedy that. The suite previously allocated to Thor might suit. The next best option would be one of the smaller guest suites on the secure levels."

"Either one's a temporary fix, but I guess it'll work. It should have good enough security to satisfy Barnes' paranoid instincts," Tony accepted the suggestion. "Let Thor know we might be temporarily using his quarters if he's not off on Asgard doing his thing, but don't give him details just yet. Standard SI information security protocols, as applied to my personal projects, also apply to this."

"I am not certain that Sergeant Barnes would be all that pleased to know you consider him one of your projects, Sir," JARVIS snarked at him.

Tony rolled his eyes. "You know what I meant. Standard media blackout protocols, too. When he shows up, I want him to be able to get in without drawing attention."


	2. Chapter 2

The four days Barnes had asked for passed quietly, for all that Tony and Steve were both incredibly edgy for that time.

Tony and JARVIS spent the days upgrading his suit and trying to work out what could possibly make vibranium vibrate; he wanted to know what the hell had happened, and how the fuck Barnes had randomly been transported to them by whatever it was. Annoyingly, though, the readings JARVIS had logged from the suit's sensors weren't good enough to pick up what had happened, and without an energy signature that matched Loki's staff, he couldn't replicate the phenomenon. Not even in his simulations. It didn't really matter what he tried, the closest he could get was a very low level power transfer between the machine and his reactor, and Steve's shield. It was on the order of nanowatts, though. Nowhere _near_ the levels of energy required to move something the mass of a human. Let alone one Barnes' size, or with a metal arm making him even heavier. Even including his readings on Loki's Glowstick of Destiny in his simulations didn't help.

The only logical conclusion he could draw, was that there was some property that power source had, which didn't show up on his scans. Without that information, all he could determine was that something utterly bizarre had happened. And, frankly, Tony rather suspected that not even the HYDRA scientists who had built the machine had known this result was possible. If they had, he was sure, they'd have tried a lot harder to capture him and Steve and put them in a room with it.

Steve, on the other hand, spent the days in the reinforced gym Tony had designed for the team. After the first day, once the sparring session that Steve had predictably strong-armed Clint into was over, JARVIS noted some minor damage to the sparring mats and ring. After the second, to the reinforced heavy bag. After the third -- Tony had yelled at him when he'd found out -- to the obstacle course. That last set of damages had resulted in a need for more than just a quick replacement part.

Steve spent the fourth day in Tony's workshop, pacing and fretting and generally driving Tony out of his mind.

"For the thousandth time, Steve, sit the fuck down. I can't think with you pacing the room like a goddamn caged wolf or whatever the expression is." Tony snapped at him when he could take no more of Steve's antsy behaviour and fidgeting. It was better than dealing with Steve's emotions -- which the man was surprisingly good at projecting all over the room -- but no less distracting.

"I can't help it," Steve protested, the pacing stopping while he was distracted by Tony's complaining, and sounded like he was actually a little apologetic.

"Honestly," Tony grumbled, "I thought you learned how to wait back in the 40s."

Steve made a face at him. "That's different. You can't compare waiting for the right time to surprise a HYDRA installation or jump out of an airplane with something like this."

"Why not?" Tony pointed at Steve with his stylus. "Seems to me it's exactly the same. This situation even includes the requisite amount of weaponry, on Barnes' part. He might show up any minute, he's likely to be edgy and ready to fight us if he has to -- you especially, and if you lose your patience you might still ruin everything if your timing is wrong."

Steve dragged his hands through his hair, which was just long enough that he could catch it in his fists and tug at it, then dropped them back to his sides and let his head fall back until he was staring at the ceiling blankly. "Yeah, sure. On the surface maybe," he managed, and at least now he was talking rather than pacing and projecting his nerves all over the workshop. After a beat Steve went on, "The emotions behind it are all wrong, though. Your analogy doesn't hold. It might feel that way to you, but to me it's like-- like sitting by a hospital bed and hoping he'll recover."

Tony blinked and focused a bit more of his attention on Steve, at that. He'd almost forgotten to consider the fact that Barnes was Steve's Rhodey. "Okay, that's fair, but pacing around my workshop isn't going to help."

Steve rubbed at the nape of his neck briefly. "I haven't found anything better."

Now that was interesting. His curiousity piqued, Tony decided to follow that line of questioning. "Not even destroying the gym?" He asked, knowing his voice had to be desert dry.

At least Steve had the decency to look abashed. "I apologised for that?"

"You did," Tony acknowledged, "and as coping methods go it's not the worst you could choose."

"Better than pacing around your workshop?" Steve inquired, a hint of a smile tugging at his lips.

"Definitely." Tony duplicated his hologram, balled one of them up, and tossed it at Steve's head. Naturally the asshole caught it before it could hit him -- and nevermind that it was just a bit of light JARVIS was projecting -- then threw it right back. Tony caught it and threw it at the target high up on the wall before he continued speaking. "Seriously, though. You need to figure out what you're going to do to handle those emotions of yours once he shows up." Tony knew he sure as hell was a fine one to talk, where it came to emotions and coping, but he did put some effort into dealing with his. "If you think waiting for him to show up is bad... that's gonna be even worse."

The quirk of Steve's lips vanished as though it had never been, and the suddenly unhappy look that replaced it almost made Tony want to take the words back. "I know, Tony. But it's still better than wondering whether he's not contacting me because he's not ready or because HYDRA managed to retake him."

Tony could only shrug. He fought to find the words to reply, only to get interrupted by JARVIS.

"Sir, I believe your guest has arrived," his AI announced.

Taking the distraction gratefully, Tony turned to JARVIS and started trying to assess the situation. "Do you have eyes on him, J?"

"I do, but I have nothing more. He is being quite careful to stay out of reach of my microphones and speakers."

Steve looked a little pained by that.

"Well, where is he?" Tony demanded, mentally evaluating whether he would need his armour. "Gimme a feed."

"Currently, he is lurking in the alley near our loading docks." JARVIS told him, opening the feed, as requested.

Steve crowded close, peering at the image, but said nothing, though he radiated tension and a need to move.

Only knowing that Barnes was present allowed Tony to spot him. The guy was good. If he want out there in his suit he'd draw attention. Hell, maybe even if he went in street clothes. "Cap," he caught Steve's eyes, "you're up."

"Huh?" Steve looked at him like he'd grown an extra head, but visibly redirected his attention toward the door. His expression didn't change much, but there was a tightness around his eyes and mouth that spoke volumes about the conflict going on between his need to go get Barnes and the sure knowledge that going out there without the relevant intel was probably not the best plan. "Why me?"

And, possibly, because of the way Barnes had insisted Steve keep out of the deal Tony had struck with him, back at the HYDRA base.

Tony shrugged and started ticking points off on his fingers. "I'm conspicuous, no matter what I wear; you're not plastered all over the news or other media constantly and the media keeps a close eye in the Tower; the paparazzi follow you around less; you're known to Barnes as, well, maybe not an ally, but part of my team and living in the building; you know a couple of the less frequently observed routes in and out of the Tower; and you can carry a comm for Barnes with you.

He suited actions to words, setting a spare comm unit to transmit and receive on only a single frequency and handing it to Steve. "Here. Go get him and bring him to the common floor."

Steve accepted the comm unit but hesitated. "And if he runs? What then, Stark? Bucky wasn't too happy to see me at that base. And now you're sending me out to talk to him?"

"Are you telling me you suddenly changed your mind about running after him and trying to force him to talk to you?" Tony gave him a wry look. "You'll have to decide if you want to try to chase him down and watch him vanish into thin air for another six months because you did, or let him run, calm himself down and come looking for me with the intent to yell at me for sending you."

Steve gave him a weirdly helpless look that reminded Tony of just how young the Cap really was. Then he headed for the door without a word.

"J, let Steve know if Barnes bolts before he gets there."

"It is likely that the Sergeant is staying out at the loading docks in the hopes of getting into the building unseen. I would estimate that he will stay where he is for quite some time if left undisturbed."

"Good," Tony replied simply. "That makes our lives easier."

There was a short silence.

Tony broke it to ask, "Think Barnes will bolt?"

"That is difficult to predict, Sir. There are a large number of variables for which we do not have values." JARVIS said after a beat.


	3. Chapter 3

Waiting for Steve to come back was a kind of painful that he hadn't experienced in a long time. If ever. Maybe that time he'd had to ask Pepper to break into his office to download Obie's ghost drive.

Tony felt like he was going to vibrate right out of his skin.

He'd seen Steve approach his friend, a lot more cautious than he'd been up until now, and offer him the comm link. After a short exchange, Steve had left the comm on the edge of the loading dock and made for the door.

Barnes hadn't moved since then.

And Steve hadn't shown up in the workshop to tell Tony how it had gone.

"Sir," JARVIS suggested, "perhaps pacing around the workshop is not the most productive use of your time."

Tony ran a hand through his hair. "You got any better ideas, buddy?"

A projection of his latest update for Clint's arrows popped up in front of him. "I believe the weight of the payload could be reduced by using molded plastic or silicone."

That… Tony considered the idea. That might even work. There didn't have to be a rigid payload casing for what he had in mind. "What about the aerodynamics?"

Somehow, he slipped smoothly into the flow of designing after that. It was kind of surprising, considering how focused he'd been on Barnes and Steve, but he was grateful for it. The opportunity to lose himself in the application of science and computational theory was always relaxing, and he'd sorely needed it.

JARVIS' first ping for his attention barely caused a ripple in his focus. The second brought him to a screeching halt.

"Sir, you have a guest," his AI announced.

"Yeah, great, sure," Tony mumbled, trying to finagle the silicone plastic hybrid coating they'd come up with into staying in place at supersonic airspeeds. It potentially had a number of applications in skydiving and marine diving tech and he wanted to try using a version of it for his undersuit layer.

"Stark," a voice he didn't automatically recognise jolted him out of his groove, "it's polite to look at someone after you invite them in."

Tony all but jumped out of his skin, and turned to glare at whoever had somehow gotten past JARVIS.

He relaxed only a hair when he spotted Barnes. "J, why didn't you tell me he was in the building?"

A hint of a smirk tugged at Barnes' features, suddenly making him look a lot more like sex on legs than a trained assassin who could break Tony in half without even trying. "I asked him not to."

And JARVIS had done it.

Tony eyed Barnes a bit critically, then gave up that fight. The potential payoff wasn't worth the effort required, and he wanted to interrogate JARVIS in peace. "And so you're here. Now what? You need something? Want something?"

That question made the smirk a little more pronounced. Tony decided he could see why Steve was so hung up on this guy. After a beat, Barnes answered. "I have what I need and you already promised me what I want," he said. "A place where I can rest."

Shutting down the design interface with a gesture to JARVIS, Tony turned to face Barnes fully. "You're allowed to want more than that, you know," he replied quietly. "You're allowed to need more than that."

Barnes said nothing, and, for all that his expression didn't change, Tony could see him clam up.

"Anyway," he added, "that's a topic that we can hash out later. JARVIS get you settled yet?"

"Settled?" Barnes looked almost baffled.

Tony raised an eyebrow at him. "I wasn't kidding about the room and board. You agreed to come here, you get a suite and access to the team facilities. The rest of the Tower is off limits, but on the secure levels you're free to come and go. No unnecessary destruction and no fighting with the team."

He got no visible response, but Tony suspected he'd caught Barnes flat-footed.

"Into the elevator," Tony ordered.

Barnes hesitated for a split second before he complied, turning to the short corridor. "And your workshop?”

"What about my workshop?" Tony asked, knowing his tone had to be a bit cold and guarded. Suspicious. But he had to be, given what he worked on in there. Tony trusted JARVIS. Knew his AI would hide anything truly sensitive from sight before allowing Barnes or anyone else without high enough clearances into the 'shop. But Obie had managed to get past JARVIS, and Tony couldn't discount the possibility that someone else might succeed.

"Is it part of the secured areas?" Barnes asked him, as they waited for the elevator doors to open.

Tony debated what to say as he stepped into the waiting elevator car. Eventually he went with, "It is, but not even the team has free access whenever they want. You want access, you ask. Every time."

That got him a thoughtful look.

Changing the subject, Tony refocused his attention on the task at hand. "JARVIS?"

"Sir?"

"Which suite's best for Barnes here?"

The car started smoothly rising. "Perhaps that previously assigned to Thor," JARVIS responded, following his lead and not revealing that they'd arranged this ahead of time. "It should be sufficiently reinforced to prevent any unintended damage, and is fully furnished."

It was also, Tony noted, as far away from his own apartments and Steve's assigned ones as it was possible to get. The only real downside was how exposed Barnes was likely to feel. "That apartment has a lot of windows."

Barnes shook his head without any prompting. "No."

"We do not have any apartments that do not have windows, Sergeant," JARVIS told him. 

Barnes growled, more or less under his breath. "I thought you said this place was secure."

Tony smirked at him. "If you'll let me, I'll show you how secure it is."

The expression on Barnes face was minimal, but it very clearly communicated how unimpressed he was with the idea of floor to ceiling windows.

The elevator car came to a halt a moment later with perfect timing, proving JARVIS could turn on a dime, and Tony led the way out assuming that Barnes would follow. JARVIS had not put them on Thor's floor after all, and Tony knew a concession when he saw one. Rolling with the change, he shrugged. "We use the suites on this level mostly for guests, when we have any, but if you decide you like it after all we'll assign the one you pick to you until such time as you no longer want it," Tony said as the door unlocked with a click. Barnes nodded, apparently counting the ability to lock the door a plus point.

Walking into the apartment as though he owned it (and, yes, technically he did) Tony went on to point out the other features of the place. "This is the suite on the floor with the fewest windows. They face north, and you don't get much sun, but I doubt that's something that would bother someone like you. You've got a small but fully furnished kitchen, a living room, a bedroom with master bath, and all the amenities that go with that. Internet, television if that's something you'd be interested in, the works. Think five star hotel, and you've got a reasonable benchmark. And as to security… well you've seen the locks on the front door. The bedroom has similar ones. Then JARVIS is constantly monitoring the building's security, and you can shut out the world anytime you please. J?"

Quicker than he could blink, the view of the city outside was replaced by a view of … Tony was pretty sure that was Switzerland. Barnes' face did something funny.

Ignoring the reaction for the moment, Tony added, explaining, "Fully responsive retro-reflective coating. You get a pretty view, and no one can see in from the outside. It creates an optical static field that blocks normal optics like cameras or scopes as well as digital ones like night vision and such."

He watched as Barnes considered that.

"I want to test it."

"The static field?" Tony thought he could see a hint of true interest in Barnes' eyes.

"Yes."

"And if you're satisfied you'll take the suite?" Tony asked him, "Just to spell everything out."

He was pretty sure Barnes came close to actually rolling his eyes.

"You're not going to let that go, are you," came the flat, slightly irritated reply.

"Nope!" Tony laughed outright at the way Barnes glared at him.

"If your static field does what you claim," Barnes told him, speaking slowly and clearly, treating him as though his IQ was about 100 points lower than it was in reality, "I'll take the suite."

"Good, then that's settled," Tony decided. "Go do your penetration testing, and move your stuff in. Get comfortable. Oh, and are you joining us for dinner?"

"Dinner?" 

"Yep, team dinner. Steve insists on them every so often, but usually no one else bothers to show up."

The prospect of possible social interaction with the team seemed to fall somewhere on the scale between terrifying and interesting. Tony could see the moment of hesitation on Barnes' part.

Terrifying seemed to win out.

"Another night."

"Then let JARVIS know what you'd like to eat and he'll see to it that it's delivered," Tony suggested. "And anything else you need, let him know. If it requires authorisation, he'll tell you so, and then it'll go by me for final approval automatically if you still want to go ahead with whatever it is."

It was more difficult than he'd thought it would be to leave the apartment for reasons he couldn't quite put his finger on, but Tony managed it. He turned and stepped back out the front door, and tossed his parting shot over his shoulder. "Let me know what you decide."


	4. Chapter 4

Four hours after he'd left Barnes in his (potential) new home, Tony was just finishing the last bites of his meal. Steve sprawled comfortably on the sofa opposite him, looking like he wanted to sleep right where he was. His team captain seemed to have run out of nerves to fray and nervous energy to sustain his pacing. Looked a lot like like he was suffering an adrenaline crash with a side of food coma, really.

Point was, it was as relaxed a moment as they ever really got, as superheros and part of the Avengers. The others had all once again chosen not to show up, for whatever reason, and Tony wasn't going to put up a fuss about that. It was kind of nice to get to spend some time with Steve where the man wasn't trying to vibrate right out of his own skin for one reason or another and they weren't on mission or trying to stave off certain doom. Times like that, he could almost let himself imagine they were in that platonic relationship Barton had tried to tease them about a few days earlier.

So of course Barnes had to shatter it.

The asshole appeared silently between one of Tony's glances around the room or at Steve and the next, making him jump out of his skin with a surprised yelp. Again.

"Oh my God," he grumbled at the smirking assassin, and took a steadying breath as Steve sat up. "Fuck you, Barnes."

"Maybe another night," Barnes shot back, calm as anything. "I'm keeping the apartment."

Tony would have replied with something appropriately scathing, but Steve got to his feet with a nearly blinding smile and derailed Tony's train of thought entirely.

"You're staying?" He asked, sounding like he was holding himself back from giving Barnes a bear hug by the skin of his teeth. Tony watched as Barnes carefully maintained the distance between them.

"For now," Barnes acknowledged, then turned and disappeared into the elevator that he must have asked JARVIS to hold for him.

Steve took the opportunity to turn that smile on him, and Tony froze.

His reaction seemed to have no effect on Steve, who took him by one hand and hauled him to his feet, then wrapped _him_ in the bear hug Barnes had dodged.

"Whoa!" Tony flailed for a moment, not sure what to think about the situation. "You, uhhh, you okay there, Steve?"

Steve shrugged. "Better than I have been in years," he replied, stopping Tony's squirming cold. "You're amazing, Tony. You gave me a chance to make up for what I said to you when we met, then threw me a raft when I was drowning, too. You gave me a home, when I had none, and now you gave me back Bucky. I never should have doubted you. You always come through on what you promise, and I've _seen_ that so many times. You come through, even if it's not in a way I'd have thought up, myself."

All Tony could say was, "Your way wasn't working? Thought this was worth a try. And he's not back yet."

This was like stepping into the Twilight Zone. Steve's broodiness, his frustration, his anger at the world, it all seemed to have vanished. Like all it took to get Steve to calm the fuck down was the presence of his old buddy Barnes. Tony wasn't sure he trusted in the tameness of _that_ wolf. 

"Doesn't matter." Steve said firmly and shook his head, his voice cracking slightly under the weight of his emotions. "I've got a better chance now than I ever have, since the moment he fell."

Tony awkwardly patted at Steve's shoulders. "You're welcome?" He said a bit uncertainly, and tried to free himself.

Tried. Steve wasn't budging.

"What is this," Tony joked, "a kidnapping?"

Steve huffed at him. "Tony, why do you think I asked you to dinner?"

It felt like a non sequitur. "If it wasn't out of a desire to get me out of my workshop, or a half-hearted attempt to have a team dinner without the team... I genuinely have no idea," he replied, still trying to get free.

In response, Steve broke the hug, but he didn't let go. "You really are as dense as Pepper likes to claim," he said on a sigh. "This wasn't a team dinner, Tony."

"Okay?" Tony thought he could see what direction this was going. He just wasn't sure he believed it. Steve wasn't generally this impulsive; that was Tony's schtick.

A warm hand came up, trailing lightly over his arm in the process, and caught his chin. Tony found himself staring Steve in the eye and had to fight not to lose himself in trying to decide what color they were. He never could quite decide whether they were blue, green, or some mix of the two. It seemed to shift with Steve's mood.

"Tell me if you don't want this," Steve said quietly, as though this moment might shatter too, were he to say it any more loudly.

As if he was going to turn that offer down.

He'd never met a bad idea he didn't like, and he knew he wasn't about to start now. Tony raised an eyebrow at Steve. "I think it'll be a disaster, but that's never stopped me before. You have issues, Steve. So do I, yeah, but at least I'm working on mine."

Steve huffed at him. "We'll see. I didn't take you for a pessimist. And the 'issues', as you call them, come with the job."

"I'm a futurist. Cynicism comes with the job," he snarked, turning the words right back around on Steve. Still not sure it was really happening, Tony reached for Steve and wrapped one of his hands around the nape of his neck. The other landed on Steve's jaw. And then they were kissing.

It was a lot more cautious than any other kiss Tony had had recently, but somehow no less intense for that. 

When they eventually pulled back, Steve cleared his throat, looking like he had no idea what to do next, but had somehow won the lottery or something else ridiculous like that. Tony smirked at him. "So… do you put out in the first date?"

"Do I-- what?" Steve stumbled over the words, then gave Tony that exasperated look he knew so well. "Tony this isn't just about sex."

It had clearly broken Steve out of his paralysis, though, and he was about to say as much when Steve pulled him back in again for another, less tentative, kiss.

He went with the demand without protest, even though this new thing between them, that they were acknowledging their apparently mutual attraction, was more than a little bit sudden. Impulsive. Tony couldn't help but feel like this was going to come back to bite him in the ass. Sure, he and Steve had probably been dancing around this little issue for months. It was obvious in the way the team ribbed them about it, but he still felt like he'd been blindsided by the change.

And Tony could see that they had been almost guaranteed to end up here, eventually... or had been, before Barnes had wound up at the Tower.

Now... he tried to bury the thought, but it came right back. Now, Steve might decide he preferred to avoid the three ring circus that came with dating Tony and take Barnes to bed instead, once he saw what he'd let himself in for.

Pulling back carefully, pleased that Steve allowed it this time, Tony cleared his throat before he realised he had no idea what to say. "Steve," he managed after a moment, "why?"

Steve looked baffled. "Why?"

Tony rolled his eyes and pulled back a little farther. "Why," he asked again. "Why me? Why now?"

"Tony," Steve replied, the baffled look vanishing under what appeared to be a mix of understanding and fond amusement, "I'm here because I want to be. I said it before: you gave me a home and reminded me to live rather than just existing. That means the world to me. We didn't get off to the best start," (Tony couldn't help himself from making a derisive sound), "but that was because I wasn't in any kind of shape to think straight."

"And you're thinking straight now?" Tony asked him. The response got him a shrug and a half smirk.

"I know you'd never believe me if I said yes. And I guess you'd be right, given that it's more 'long bisexual lines than straight ones."

Tony all but choked on his next inhalation. "Good one," he conceded. "I didn't think you knew those words."

"I'm not the straight-laced puritan everyone seems to think I am," Steve shot back. "I know plenty. You done? Or you got an objection based on something factual, rather than more assumptions and conjecture?"

Tony gave in. "You still need to work on those issues of yours."

"We can hash that out later. Answer the question, Tony."

"Guess I'm done." Tony smirked at his team captain and possible significant other. "Does that mean we're dating?"

Steve laughed at him outright. "Yeah, Tony, it means we're dating."


	5. Chapter 5

He still wasn't quite over his reactions to the kiss and discussion much later that night... well, okay, stupidly early the following morning, really, when Barnes asked to be let into the workshop.

"Sir, Sergeant Barnes is requesting entrance," JARVIS informed him.

Tony blinked, surprised. "Huh?"

JARVIS reiterated in the form of a question. "Shall I let him in, Sir?"

Looking over at the door, Tony caught sight of Barnes, standing almost hesitantly by, watching him closely. Barnes' expression looked almost pleading. Biting down on his curiosity, Tony nodded. "Alright, J."

Barnes came in, looking around warily and cataloging everything he saw. Tony watched him in turn for a few seconds, before he prompted, "Needed something?"

The question got him a vaguely startled look, followed by a shrug. "Couldn't sleep. Why aren't you in bed?"

Tony wasn't sure whether the implied 'with Steve' was only in his imagination. He decided to ignore it, in favor of holding up his gauntleted left hand. "Working on stuff. Upgrades."

Barnes gave him a nod, and went back to prowling around the 'shop. Tony knew JARVIS would keep a wary eye on Barnes, so he allowed it, turning back to his design specs. There was still something ever so slightly off about this iteration of the gauntlet armour, and he wanted to figure out what. It suddenly felt clunky somehow, as though he was back in the Mark I, for all that the changes he'd made -- to the Mark VII -- had been minor.

The silence between them hung heavy in the air, but both of them ignored it. Tony was awkward if he didn't know what to say to someone, but Barnes seemed to expect that and take it in stride.

Eventually, about fifteen minutes after he'd come in and apparently satisfied that he'd memorised the 'shop, Barnes approached him. "Stark," he opened, then paused.

Tony turned to him and raised an eyebrow. "Decided you needed something after all?"

"Yeah," Barnes replied easily, jumping on the question as though Tony'd said something Barnes couldn't articulate. "Something to do. With my hands. Tools. Something. I--"

Well. That was unexpected. Tony decided to roll with the request. It seemed harmless enough. Barnes was more than enough of a threat even bare handed; if he wanted Tony dead, it would happen regardless of whether Tony handed him a screwdriver. "Like what?"

The question made Barnes stall out again and this time he stared helplessly at Tony.

After a second or so of that, Tony gave in. Jesus, was this where Cap had learned his devastating doe-eyes? Barnes looked like he was caught somewhere between despair, frustration, and something else harder to pin down, and it lent him an air of... Not quite loneliness, no, it was far wilder than that. And it wasn't desperation. Not exactly. More like he was drowning and had no idea how to swim. 

Shaking his head to clear it, Tony reminded himself that this guy was a paranoid ex-HYDRA assassin and could kill him with one hand tied behind his back. "Alright, Terminator," he said, masking his own reaction with a grumble, "sit your ass down at the workbench."

He needed something to give Barnes to mess with that wouldn't give too much away.

Before busying himself with that, he pointed out the tool chest and other assorted supplies in easy reach, though he suspected Barnes already knew that almost as well as he did, with the possible exception of the specific contents of the drawers. "Tools and stuff are here, help yourself, but put them back once you're done. Clean, preferably."

Having said that, he didn't stick around to watch Barnes open the tool chest and systematically catalogue what was in there, too. Finding the motorcycle engine he'd been considering restoring for Steve and dropping it on the workbench in front of Barnes was oddly easy.

Tony didn't know how to feel about any of this.

When Steve showed up four hours later, recruited Barnes to his cause, and coerced Tony out of the workshop, he still didn't. The whole thing was every flavor of weird, but it had felt like it had helped Barnes.

Steve said nothing about their all-nighter though, to Tony's surprise. Simply fed them and hauled Tony off to bed.

For his part, Tony assumed that would be the end of it. He slept, knowing that he needed it even if the nightmares made it more or less impossible.

He was back on his feet a few hours later, and decided to go right back to his workshop. He hadn't worked out the issue with that gauntlet yet, after all.

Steve didn't take that lying down, though. Apparently now that they were acknowledging the crackling tension between them, anything was fair game. He fished Tony out of the 'shop again, for a 'date' on the roof of the Tower.

Needless to say, Tony balked the moment he figured it out -- which had been after Steve had gotten him more or less to the roof access door of the north stairwell. He wasn't all that fond of the rooftop, after the way Loki had hijacked it for his portal machine. Not taking no for an answer, Tony turned around and headed back down to his penthouse without a word, ignoring Steve's questions as they flowed around and over him. What Steve was saying took second or maybe fifth priority right then. Tony was more concerned with not having the panic attack he could feel himself skirting the edges of. The nightmares that had woken him had left him twitchy as hell and off-balance.

When the door to his penthouse came into view what felt like miles of stairs later, Tony took one look at it and changed his mind, heading for the communal levels instead and finding a defensible spot to wedge himself into.

Steve was still stumbling over apologies and berating himself for not thinking when Barnes entered the room and all but tripped over them. Rolling his eyes and effortlessly taking charge, Barnes sent Steve back up to the roof to pick up after himself, then -- to Tony's shock -- went into an easy crouch in front of him where he sat slumped on his sofa and caught his eyes. "You alright, Stark?"

Tony huffed at him. "Been better," he managed to rasp, "been worse."

The statement got him a nod and a hint of a smirk. "Need something?"

Feeling the echoes of their night in the 'shop for all that the roles were reversed, Tony could only stare helplessly at him. Was this how Barnes had felt at the time?

"I know what it's like to fight your own mind and memories," Barnes offered after a beat. "You need calories and sleep."

"Can't." Tony got out.

"I know," Barnes shot back. "But you gotta."

Struck to the bone by the sympathy, Tony nodded, a tiny, short, jerky motion. "I know."

Of course, that was the moment Steve burst back in, all worry and frantic words, and the moment shattered.


	6. Chapter 6

Slowly, over the next few weeks, the three of them settled into a sort of routine. Steve kept trying to take Tony on dates, though none of them involved leaving the Tower. Barnes kept finding ways to calm him down, when he was having his anxiety attacks.

Tony... wasn't sure how to feel about any of it, really, but he was enjoying himself regardless. So he decided to let things play out.

Barnes had fairly quickly finished restoring the engine Tony had more or less flung at him, then graduated to slightly more complex projects. Tony had given him a prototype comm to play with -- which he'd gotten bored of, himself -- then an old upgrade to Butterfingers' chassis that was obsolete but should be interesting to Barnes.

Just over a month after he'd joined them in the Tower, Barnes became Bucky, and Tony realised he was starting to trust the guy. Really trust him, not just accept him as reliable on Steve's say-so.

It was kind of frightening. Bucky had gotten under his skin, though, with his stupidly handsome face, his slowly improving confidence, and his apparent interest in all things mechanical.

Steve had had nothing but praise for him on the topic, either. Seemed to think that Tony was singlehandedly responsible for Bucky's recovery.

Personally, Tony doubted that was the case.

The day he found himself handing over his old arc reactor -- the one he'd built in Afghanistan -- for Bucky to tinker with, though. Shit. That had been a series of revelations. Tony'd only realised what he'd done after he'd handed it to Bucky. He'd acted without really paying attention to what his hands were doing, immersed in what he was working on in that moment, and then freaked himself right the hell out once it had dawned on him just what he'd given Bucky. He'd blurted something out that he didn't remember in the next moment, and grabbed for it, successfully snatching it back out of Bucky's startled hands.

What had to be at least half an hour later, he'd found himself curled around the thing, on the concrete floor of his workshop, with Bucky's arms wrapped tightly around him.

"Hey," Bucky asked him, apparently psychic and able to tell when Tony was able to think halfway rationally again, "you okay, Tony?"

"Sure, peachy," he rasped, carefully ignoring the way being securely wrapped up in his lover's best friend's arms was making him feel warm and safe. He was with Steve, he reminded himself. He didn't need more. Wouldn't let himself screw that up. Letting himself get too attached to Bucky was a guaranteed recipe for disaster. He wasn't the best with people or relationships, but he just knew that would end badly for all three of them.

"Never seen you react like that around your own projects before," Bucky said slowly. "What brought that one on?"

"Not sure," Tony lied, then cleared his throat, "but it's over now. You can let go of me."

Bucky made a skeptical sound, a deep rumble in his chest, but he let go.

Tony immediately missed the warmth and strength.

An almost tense silence reigned for a few seconds, then Bucky told him, "I'll let it go this time, Tony, but if it happens again, I'm not gonna let you bury your head in the sand."

Giving Bucky a tired smirk, Tony winked at him and pushed himself to his feet. "I'd have to have some sand, to do that. And as you see..." he gestured broadly to the workshop, "I don't."

Huffing at him, Bucky held out his hand. "Fine. Gonna let me play with that little trinket of yours now?"

Damn the man; he was too clever for his own good.

Tony could tell Bucky suspected the reactor had caused the panic attack, and in a way it had. He was forcing Tony to repeat the action that had set him off in the first place, but being subtle about it. Unable to keep the reactor without looking like he was going back on his initial offer to let Bucky mess around with the thing -- with his metaphorical heart, thanks for that bit of imagery, Pepper -- Tony did his damnedest to keep his body language casual.

At least the upgrades he'd made in subsequent iterations had changed the design enough that handing Bucky that version wouldn't give away all the secrets of how it worked. It was way more than he was comfortable with letting another living human see -- much less a smart one like Barnes -- but he couldn't say no without explaining why, and that was just as awkward. Nope.

"Here, knock yourself out," he said, and tossed the damned thing at Bucky, who caught it deftly and winced slightly at the clang it made as it hit his left hand. Maybe that would satisfy him.

Tony suspected it wouldn't.

The man was like a dog with a bone, when it came to things he considered mysteries.

Thankfully, after that, he managed to lose himself in his own projects, and Bucky let him be for a few hours.

For all that he was a lot calmer once Bucky dragged him away from his interfaces to have dinner with Steve, Tony spent the meal on edge and he could tell the others noticed. He didn't remember a word of the conversation afterward, either, and took the opportunity to retreat into his workshop again. He needed some time to get his balance back. The realisation that he had gotten comfortable enough with Bucky to let him learn the secrets of something as vital to his existence as the arc reactor had shaken him to an extent he hadn't expected. The thought had hit him almost as hard as Obie's betrayal for all that it didn't have the sheer amount of baggage tied to that particular memory.

"Sir?" JARVIS prompted him sometime later, "Captain Rogers is requesting entrance."

Well, he had to face the firing squad at some point. Tony winced, then pulled his media mask on as best he could. "Let him in."

Steve stepped through the door, looking almost like he was unsure of his welcome, then consciously straightened his back and squared his shoulders. "Tony? Is everything alright? Bucky said you had a rough afternoon."

Laughing and knowing it had to sound just slightly hysterical, Tony turned his back to his design interface and let himself lean one hip casually against the edge of the table. Well, as casually as he could manage anyway. "Just some bad memories. It's happened before, and it'll happen again. It wasn't his fault, if that's what he sent you down here for."

Steve's lips quirked, and Tony knew he'd guessed right. "He suggested I should check on you, yeah," Steve admitted, daring to come closer and offer a hand.

Relaxing slightly, Tony let himself take it. That simple gesture had taken him a while to get comfortable with, and Steve knew as much, but they'd more or less reached an understanding.

Until now anyway.

The skin contact helped, though. Tony felt himself calm further.

"Something else is bothering you," Steve said, breaking the silence that had built between them and making Tony tense up. "And it's something you think will upset me," he guessed shrewdly when Tony didn't reply.

Steve used his free hand to tilt Tony's head gently until their eyes met. "We disagree on a lot," he added, "I know that. But just because we disagree doesn't mean we can't find a solution. You're used to solving engineering problems. To being the only one who sees a problem and picking what you think is the optimal solution. But people don't work that way."

Tony had no idea how to respond to that little speech. "Uhhh. You've lost me."

Steve laughed, and tugged him toward his sofa, tucked away in a corner of the workshop that didn't see much traffic. He didn't speak until they were comfortably settled, with Tony sprawled across his chest and wrapped up in his arms. "Tony, talk to me? Tell me what's going through that head of yours. I'm not even going to try guessing; I'm always wrong."

Suddenly faced with the dilemma of trying to articulate something he'd been avoiding thinking about, Tony froze.

Steve waited him out, and Tony could see what it was costing him to keep his mouth shut. Could see the tightness that reminded him of the day Barnes had shown up at the Tower. And the way Steve bit at the inside of his lower lip but made sure it didn't show much, in what was doubtless an old, old habit.

That carefully controlled, tightly leashed emotion was what decided Tony, in the end.

With a sigh, he let his head fall forward to rest on Steve's shoulder. "I think I might be falling for Bucky, but I sure as fuck don't want to break this off," he said bluntly, deciding to go for broke.

There. It was out in the open.

If Steve was going to end things, Tony knew, it would hurt a lot less now than later.

Steve was silent for a few seconds that felt more like hours, obviously choosing his words carefully.

"Okay," he said, eventually.

"Okay?" Tony pushed himself up enough that he could look Steve in the eyes and glare at him. "I spill my guts and all you can say is 'Okay'? And why aren't you pissed? Normal people get upset about that kind of thing."

Steve, the asshole, smirked up at him. "I'm dating Tony Stark. Do you really think I went into this with the expectation that you'd never think about anyone else ever again in your life? You've been all over the gossip rags in who knows what kinds of orgies, and the more believable news in more than one threesome. You'd have to say far worse than that to scare me off."

Tony gaped at him.

"I've told you before: I'm not as straight-laced as everyone thinks. Including you, apparently. And I considered asking Buck if he was interested before he fell. It never felt like quite the right time, after we got him back." Steve added with a shrug, as though he hadn't just shattered all of Tony's expectations twice over. "We'll take it slow and see how things go. Maybe someday we can invite Bucky to have some fun, maybe not. But right now it's you I'm with, and I don't want to lose you either. Not to anyone else, not to your own doubts, not to your ideas of what I might think."

There wasn't much he could say to that, so Tony rolled his eyes at the ridiculously open-minded moron he'd ended up dating, and settled back down against Steve's chest then closed his eyes. "Fine, we'll see how it goes."


	7. Epilogue

Three weeks later, they were still fine, and Tony was finally starting to believe Steve had meant what he'd said.

He was back in the 'shop and Bucky had followed him there on the heels of what Tony suspected had been a sleepless night due to nightmares. Handing Bucky a slightly newer iteration of the reactor to mess with while he debugged another update to his gauntlets and tested them against his practice dummies, Tony kept a careful eye on him.

The third time he checked on his guest, Tony smiled to see that he'd passed out at the workbench, his head pillowed on his right arm.

"DUM-E," he said quietly, making sure not to raise his voice above the mutter he'd been using to talk to JARVIS, "get a blanket for him. U, you're on cleanup duty. Pick up those wrenches he left next to the Mercedes." Something he couldn't name, some vague feeling of warmth and want, made him watch Bucky for a couple of minutes before he went back to what he was doing. "J, ask Steve to put Barnes to bed if he doesn't wake up in half an hour."

"Of course, Sir. And might I suggest you adjust the torque on the actuators for the left forefinger?"

Tony turned back to his upgrades, a buoyant feeling of hope making him imagine a future for the three of them that actually made them all happy. It wasn't likely to actually be that easy, but a man could hope.


End file.
